Wireless communication is commonly carried out over a network or system that, in general, can be characterized as having a base station and a plurality of remote stations that communicate wirelessly with the base station. Although a wireless communication system is not constrained by the need for wired connections, the system nevertheless does face resource constraints in supporting the wireless communications of the plurality of remote stations. A wireless system transmits data over channels within a band of frequencies (i.e., bandwidth). A wireless frequency band has a limited amount of bandwidth, however. Accordingly, some manner of allocating resources among the plurality of remote stations is needed if the system is to transmit data efficiently.
Efficient data transmission requires not only that resources be allocated among the plurality of remote stations, but also that transmissions be scheduled so as to address another physical limitation to wireless communication: signal fading. Signal fading impedes transmission and stems from at least two sources, namely, obstacles near a station that is receiving transmission (i.e., shadowing fading) and the cumulative effect due to scatters, reflectors and diffractors surrounding a station that is receiving or transmitting (i.e., multi-path fading).
So-called “opportunistic communication” turns the limitation of signal fading into an opportunity by always serving the remote station with the strongest channel, diverting bandwidth if the channel is fading. To exploit changing channel fading conditions, each remote station measures its signal strength and transmits that information to the base station. The base station allocates available resources according to a scheduling algorithm based on this transmitted information.
Over time, though, resources should be allocated so that no one station continuously receives all the resources. One approach, therefore, is to allocate communication resources on the basis of a so-called proportional fair algorithm. Such an algorithm is intended to allocate communication resources among multiple users more fairly than would a simple first-come-first-served queuing algorithm. A fair algorithm has also been shown to more efficiently utilize fading channel variations at a mobile receiver.
Such allocations, however, do not provide providers of wireless communication services with sufficient control over data transmission to meet all service provider requirements. There remains, for example, the problem of constraining the data throughput of those users that put excessive demands on a wireless communications network. There is also the problem of differentiating among users on the basis of the nature of the application for which each user is utilizing the network. Further, there is the problem of differentiating among network users on the basis of individual users' payment plans. Conventional schemes for allocating the transmission of data do not adequately address these and other service provider requirements.